Ambient or conditioned air may be channeled from one area of a vehicle to another via a return air duct. For example, the return air duct may direct heated, cooled, and/or humidified air from one portion of the vehicle, such as an instrument panel, to another portion of the vehicle, such as a rear passenger footwell. Often, a path or routing for the return air duct through the vehicle is circuitous, because of obstacles such as seating hardware, electronics, structural components, and the like.